Gas sensor and packaging method thereof

Abstract

The invention discloses a gas sensor and a packaging method thereof, and relates to the technical field of sensors. The gas sensor comprises a shell, an oil-gas separation assembly and a detection main body, wherein the shell is provided with an inner cavity and a detection port communicated with the inner cavity; the oil-gas separation assembly comprises a base and an oil-gas separation membrane, the base is arranged in the inner cavity, the oil-gas separation membrane is arranged on the side, facing the detection opening, of the base and blocks the detection opening, and the oil-gas separation membrane is configured to prevent oil from passing through and allow to-be-detected gas to pass through; the detection body is arranged in the inner cavity and located on the side, away from the detection opening, of the oil-gas separation assembly, the detection body comprises an electrolyte, a working electrode, a reference electrode and a counter electrode, the working electrode, the reference electrode and the counter electrode are arranged in the electrolyte, the working electrode is arranged at the end, close to the detection opening, of the electrolyte, and the reference electrode and the counter electrode are arranged at the end, away from the detection opening, of the electrolyte. The gas sensor can be directly immersed in oil liquid for gas detection, the degassing process is omitted, and high efficiency and reliability are guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of sensor technology, and in particular to a gas sensor and a packaging method thereof. Background Art

[0002] The reliable and safe operation of oil-filled electrical equipment such as transformers, reactors, mutual inductors and bushings is the key to ensuring efficient power generation, transmission and distribution. When mechanical failure, thermal failure, discharge failure or oil or paper aging occurs inside the equipment, various characteristic gases will be generated and dissolved in the oil. Timely and effective detection of the fault gas content in the oil can greatly reduce the occurrence of accidents.

[0003] In the existing technology, electrochemical sensors have potential advantages due to their small size and fast response. However, traditional electrochemical sensors face packaging problems when used in oil-immersed environments. They cannot directly contact the oil and are prone to gas loss or contamination during the degassing step, affecting the accuracy and reliability of detection. Summary of the invention

[0004] The purpose of the present invention is to provide a gas sensor and a packaging method thereof, which can be directly immersed in oil to detect gas, eliminating the degassing process and ensuring higher efficiency and reliability.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A gas sensor for detecting parameters of gas in oil, comprising:

[0007] A shell, wherein the shell is provided with an inner cavity and a detection port connected to the inner cavity;

[0008] An oil-gas separation component, comprising a substrate and an oil-gas separation membrane, wherein the substrate is disposed in the inner cavity and is a loose and porous structure, the oil-gas separation membrane is disposed on a side of the substrate facing the detection port and blocks the detection port, and the oil-gas separation membrane is configured to block the oil from passing through and allow the gas to be detected to pass through;

[0009] The detection body is arranged in the inner cavity and located on the side of the oil-gas separation component away from the detection port. The detection body includes an electrolyte and a working electrode, a reference electrode and a counter electrode arranged in the electrolyte. The working electrode is arranged at one end of the electrolyte close to the detection port, and the reference electrode and the counter electrode are arranged at one end of the electrolyte away from the detection port.

[0010] As an optional solution of the above-mentioned gas sensor, the microstructure of the oil-gas separation membrane is a covalent organic framework structure, and the covalent organic framework has molecular pores, the molecular pores are larger than the molecules of the gas, and the molecular pores are smaller than the molecules of the oil.

[0011] As an optional solution of the above-mentioned gas sensor, the gas sensor further includes a protective film, which is arranged between the oil-gas separation component and the detection body, and the protective film is configured to block the electrolyte from passing through and allow the gas to be detected to pass through.

[0012] As an optional solution of the above-mentioned gas sensor, fixing structures are provided on opposite sides of the protective film, and the fixing structures include a fixing net, and the fixing net is fixedly connected to the protective film.

[0013] As an optional solution of the above-mentioned gas sensor, the fixing structure further includes a sealing member, and the sealing member is arranged around the outer circumference of the fixing net to seal and connect the fixing net and the side wall of the inner cavity.

[0014] As an optional solution for the above-mentioned gas sensor, the shell includes a top surface and a bottom surface arranged opposite to each other, the detection port is opened on the top surface, and along the direction from the top surface to the bottom surface, the projection of the fixed net on the bottom surface is located within the projection of the working electrode on the bottom surface.

[0015] A packaging method for a gas sensor, the packaging method is used to manufacture the gas sensor, the packaging method comprising:

[0016] Obtaining a substrate;

[0017] Cleaning the substrate with anhydrous ethanol;

[0018] Drying the substrate at a constant temperature for a first period of time;

[0019] The oil-gas separation membrane is coated on the surface of the dried substrate.

[0020] As an optional solution of the packaging method of the gas sensor, coating the oil-gas separation membrane includes:

[0021] Coating the substrate using a spin coater;

[0022] Controlling the rotation speed of the spin coater to a first rotation speed and maintaining it for a second time period;

[0023] Controlling the rotation speed of the spin coater to a second rotation speed and maintaining it for a third time period;

[0024] Repeat the above steps several times to complete the coating of the oil-gas separation membrane.

[0025] As an optional solution of the packaging method of the above-mentioned gas sensor, the packaging method further includes:

[0026] Allowing the substrate coated with the oil-gas separation membrane to stand for a fourth period of time;

[0027] The substrate is dried at a constant temperature for a fifth period of time.

[0028] As an optional solution of the above-mentioned gas sensor packaging method, the first rotation speed is less than the second rotation speed; and / or

[0029] The second duration is shorter than the third duration.

[0030] Beneficial effects of the present invention:

[0031] The present invention provides a gas sensor and a packaging method thereof. The gas sensor comprises a housing, an oil-gas separation component and a detection body, wherein the housing is the overall support structure of the gas sensor, and the oil-gas separation component can separate the oil and the gas in the oil, can isolate the oil and allow the gas to pass through the oil-gas separation component, so that the gas moves to the working electrode of the detection body, and detects the composition and content of the gas in the oil through the electrochemical reaction between the gas and the working electrode. Due to the presence of the oil-gas separation component, the gas sensor can be directly immersed in the oil to detect the gas, eliminating the degassing process and ensuring high efficiency and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a schematic diagram of the structure of the gas sensor provided by the present invention;

[0033] Figure 2 It is a molecular structure diagram of the oil-gas separation membrane provided by the present invention.

[0034] In the figure:

[0035] 1. Shell; 11. Detection port; 12. Top surface; 13. Bottom surface;

[0036] 2. Oil-gas separation component; 21. substrate; 22. oil-gas separation membrane;

[0037] 3. Detection subject; 31. Electrolyte; 32. Working electrode; 33. Reference electrode; 34. Counter electrode;

[0038] 4. Protective film;

[0039] 5. Fixed structure; 51. Fixed net; 52. Sealing element. DETAILED DESCRIPTION

[0040] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0041] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0042] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] Unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include the first feature being in direct contact with the second feature, or may include the first feature being in contact with the second feature through another feature between them instead of being in direct contact. Moreover, a first feature being "above", "above" and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0044] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0045] Embodiment 1

[0046] This embodiment provides a gas sensor for detecting parameters of gas in oil, wherein oil refers to insulating oil, which is generally used in oil-filled electrical equipment such as transformers, reactors, mutual inductors and bushings to play a role in cooling and insulation, and gas parameters generally refer to the type and content of the gas.

[0047] like Figure 1 As shown, the gas sensor includes a shell 1, an oil-gas separation component 2 and a detection body 3, the shell 1 is provided with an inner cavity and a detection port 11 connected to the inner cavity, the oil-gas separation component 2 includes a substrate 21 and an oil-gas separation membrane 22, the substrate 21 is arranged in the inner cavity and has a loose porous structure, the oil-gas separation membrane 22 is arranged on a side of the substrate 21 facing the detection port 11 and blocks the detection port 11, and the oil-gas separation membrane 22 is configured to block the oil from passing through and allow the gas to be detected to pass through.

[0048] The housing 1 of the gas sensor is the overall supporting structure of the gas sensor, which can support and protect the internal structure. The oil-gas separation component 2 can separate the oil and the gas in the oil, isolate the oil and allow the gas to pass through the oil-gas separation component 2, so that the gas moves to the detection body 3 to detect the composition and content of the gas in the oil. Due to the presence of the oil-gas separation component 2, the gas sensor can be directly immersed in the oil to detect the gas, eliminating the degassing process and ensuring high efficiency and reliability.

[0049] For ease of description, the housing 1 includes a top surface 12 and a bottom surface 13 that are oppositely disposed. The detection port 11 is opened on the top surface 12 , and the detection body 3 is disposed in the inner cavity and connected to the bottom surface 13 .

[0050] In this embodiment, the detection body 3 is arranged in the inner cavity and is located on the side of the oil-gas separation component 2 away from the detection port 11. The detection body 3 includes an electrolyte 31 and a working electrode 32, a reference electrode 33 and a counter electrode 34 arranged in the electrolyte 31. The working electrode 32 is arranged at one end of the electrolyte 31 close to the detection port 11, and the reference electrode 33 and the counter electrode 34 are arranged at the end of the electrolyte 31 away from the detection port 11.

[0051] The reference electrode 33 is used to provide a known and stable potential as a reference standard for measurement; the main function of the counter electrode 34 is to form a current loop to ensure the smooth flow of current on the working electrode 32; and the working electrode 32 is the place where the electrochemical reaction occurs with the gas to be detected, and the process and mechanism of the electrochemical reaction are studied by observing the current changes on the working electrode 32. The working electrode 32 is usually made of conductive materials, such as platinum, gold or glassy carbon, and its surface needs to be polished and processed to ensure the accuracy of the reaction.

[0052] In this embodiment, the microstructure of the oil-gas separation membrane 22 is a covalent organic framework structure, and the covalent organic framework has molecular pores, which are larger than gas molecules and smaller than oil molecules. Figure 2As shown, the covalent organic framework structure refers to that the molecular composition of the oil-gas separation membrane 22 is a polymerized structure, and the main structure forms a ring. Multiple rings are aggregated to form the macroscopic structure of the oil-gas separation membrane 22. The middle of the ring is a molecular pore. By controlling the conditions of the chemical reaction, the molecular pores of the covalent organic framework structure can be adjusted as needed to ensure that the molecular pores are larger than the gas molecules to ensure that the gas molecules can pass through the oil-gas separation membrane 22. At the same time, the molecular pores are smaller than the oil molecules to ensure that the oil molecules will be blocked by the oil-gas separation membrane 22, thereby achieving the effect of oil-gas separation.

[0053] Specifically, the material of the oil-gas separation membrane 22 is Teflon AF2400.

[0054] like Figure 1 As shown, the gas sensor further includes a protective film 4, which is disposed between the oil-gas separation component 2 and the detection body 3, and is configured to block the passage of the electrolyte 31 and allow the gas to be detected to pass through. The protective film 4 is used to isolate the electrolyte 31 from the oil-gas separation component 2, to prevent the electrolyte 31 from reacting with the substrate 21, thereby preventing the electrolyte 31 from being contaminated and the substrate 21 from being corroded, and to ensure the purity of the gas detection environment.

[0055] Furthermore, a fixing structure 5 is provided on opposite sides of the protective film 4, and the fixing structure 5 includes a fixing net 51, and the fixing net 51 is fixedly connected to the protective film 4. The fixing net 51 can protect and support the protective film 4 on the one hand, and can also prevent the detection body 3 from being subjected to external impact and physical damage on the other hand.

[0056] In this embodiment, the fixing structure 5 further includes a sealing member 52, which is arranged around the outer periphery of the fixing net 51 to seal and connect the fixing net 51 with the side wall of the inner cavity. The sealing member 52 can connect the fixing net 51 with the housing 1. By setting the sealing member 52, a fixing net 51 of suitable size can be selected for fixed installation, so that the size of the gas passing interface meets the design requirements. Among them, the fixing net 51 is a steel net, which can ensure strength and avoid corrosion.

[0057] Furthermore, along the direction from the top surface 12 to the bottom surface 13, the projection of the fixed net 51 on the bottom surface 13 is located within the projection of the working electrode 32 on the bottom surface 13. In other words, the working electrode 32 can cover the fixed net 51, ensuring that the gas entering the housing 1 through the oil-gas separation membrane 22 can contact the working electrode 32, thereby improving the conditions for quantitative analysis of the gas.

[0058] like Figure 1As shown, the reference electrode 33 and the counter electrode 34 are arranged close to the bottom surface 13, and the working electrode 32 is arranged close to the detection port 11, and along the direction from the top surface 12 to the bottom surface 13, the distance between the working electrode 32 and the reference electrode 33 is equal to the distance between the working electrode 32 and the counter electrode 34. The working electrode 32 is as far away from the reference electrode 33 and the counter electrode 34 as possible, which can avoid the reaction of the working electrode 32 from affecting the reference electrode 33 and the counter electrode 34 to the greatest extent, thereby ensuring the accuracy of the detection result.

[0059] Embodiment 2

[0060] This embodiment also provides a gas sensor packaging method for manufacturing the above-mentioned gas sensor, the packaging method comprising:

[0061] Obtaining a substrate 21;

[0062] Cleaning the substrate 21 with anhydrous ethanol;

[0063] Drying the substrate 21 at a constant temperature for a first time period;

[0064] The oil-gas separation membrane 22 is coated on the surface of the dried substrate 21 .

[0065] The substrate 21 is a loose and porous ceramic material. Anhydrous ethanol can clean the substrate 21 to clean the debris on the substrate 21. Then, the substrate 21 is dried and kept warm in a constant temperature box to make it meet the requirements for coating the oil-gas separation membrane 22.

[0066] It is worth noting that the use of anhydrous ethanol to clean the substrate 21 is ultrasonic cleaning, and the cleaning time is 8min to 12min. The debris in the pores of the substrate 21 can be separated from the substrate 21 by vibration to ensure clean cleaning, and the temperature of the constant temperature drying is 80°C to 90°C, and the first duration is 100min to 140min. This temperature can dry the alcohol without damaging the substrate 21, and the drying efficiency is relatively suitable. Specifically, the temperature of the constant temperature drying can be 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C or 90°C, the ultrasonic cleaning time can be 8min, 8.5min, 9min, 9.5min, 10min, 10.5min, 11min, 11.5min or 12min, and the first duration can be 100min, 105min, 110min, 115min, 120min, 125min, 130min, 135min or 140min.

[0067] Further, coating the oil-gas separation membrane 22 includes:

[0068] Coating the substrate 21 using a spin coater;

[0069] Controlling the rotation speed of the spin coater to be a first rotation speed and maintaining it for a second time period;

[0070] controlling the rotation speed of the spin coater to be a second rotation speed and maintaining it for a third time period;

[0071] Repeat the above steps several times to complete the coating of the oil-gas separation membrane 22 .

[0072] The substrate 21 is adsorbed on the vacuum chuck of the spin coater. When the rotation speed of the spin coater is the first rotation speed, the covalent organic framework coating solution is evenly dripped on the surface of the ceramic substrate 21. When the rotation speed of the spin coater is the second rotation speed, the solution is dispersed to ensure that the coating forms a uniform film on the surface of the ceramic substrate 21. Repeating several times can not only ensure that the oil-gas separation membrane 22 has sufficient thickness and is not easy to be damaged, but also ensure the uniformity of the thickness of the oil-gas separation membrane 22, so that the permeability of each part remains consistent. The number of repetitions is 3 to 5 times, and the coating of the oil-gas separation membrane 22 of sufficient thickness can be completed.

[0073] In order to ensure that the solution of the covalent organic framework coating can be stably dripped onto the substrate 21 and evenly spread to form the oil-gas separation membrane 22, the first rotational speed is smaller than the second rotational speed. The first rotational speed is smaller, so that the solution can cover the surface of the substrate 21, while the second rotational speed is larger, so that the solution can flow toward the periphery and separate from the substrate 21 under the action of centrifugal force, so that the solution on the substrate 21 becomes evenly thinner, thereby forming a thin film with uniform thickness. After repeated multiple times, an oil-gas separation membrane 22 with relatively suitable and uniform thickness is formed.

[0074] Specifically, the first rotation speed is 80rpm to 120rpm, which can ensure that the solution is evenly dripped on the surface of the substrate 21 and prevent the solution from being thrown away. The second rotation speed is 450rpm to 550rpm. At this rotation speed, the solution can partially adhere to the surface of the substrate 21 to ensure the formation of the film layer. Among them, the first rotation speed can be 80rpm, 85rpm, 90rpm, 95rpm, 100rpm, 105rpm, 110rpm, 115rpm or 120rpm; the second rotation speed can be 450rpm, 460rpm, 470rpm, 480rpm, 490rpm, 500rpm, 510rpm, 520rpm, 530rpm, 540rpm or 550rpm.

[0075] In some embodiments, the second time length is shorter than the third time length. The second time length is shorter because it does not take too long to drop the solution on the surface of the substrate 21, as long as the solution covers the surface of the substrate 21, so efficiency needs to be improved; and the third time length is longer because the thickness of the film layer formed on the substrate 21 is smaller and more uniform, and the quality of the film layer needs to be guaranteed.

[0076] Specifically, the second time length is 15s to 25s, which can ensure that the solution covers the surface of the substrate 21. The third time length is 50s to 70s, under which the excess solution will be thrown off and separated from the substrate 21, and the film thickness on the substrate 21 is thin and uniform, and the film quality is good. Among them, the second time length can be 15s, 16s, 17s, 18s, 19s, 20s, 21s, 22s, 23s, 24s or 25s; the third time length can be 50s, 55s, 60s, 65s, or 70s.

[0077] After coating the oil-gas separation membrane 22 on the substrate 21, the packaging method further comprises:

[0078] Allowing the substrate 21 coated with the oil-gas separation membrane 22 to stand for a fourth period of time;

[0079] The substrate 21 is dried at a constant temperature for a fifth period of time.

[0080] The substrate 21 coated with the oil-gas separation membrane 22 is left to stand to solidify the membrane layer on the substrate 21, and then dried at a constant temperature in a constant temperature box to obtain an oil-gas separation component 2 with high oil resistance and chemical stability.

[0081] In this embodiment, the fourth time length is 10h~14h, which can ensure the solidification of the oil-gas separation membrane 22 and make the structure of the oil-gas separation membrane 22 stable. The constant temperature drying temperature is 100℃~140℃. The fifth time length is 10h~14h, so as to ensure the stability of the oil-gas separation membrane 22 itself and the stable connection between the oil-gas separation membrane 22 and the substrate 21.

[0082] Specifically, the fourth duration can be 10h, 10.5h, 11h, 11.5h, 12h, 12.5h, 13h, 13.5h or 14h; the constant temperature drying temperature can be 100℃, 105℃, 110℃, 115℃, 120℃, 125℃, 130℃, 135℃ or 140℃; the fifth duration can be 10h, 10.5h, 11h, 11.5h, 12h, 12.5h, 13h, 13.5h or 14h.

[0083] After the detection body 3 is arranged in the shell 1, and the fixed structure 5, the protective film 4, and the fixed structure 5 are arranged in sequence along the direction close to the detection port 11, the oil-gas separation component 2 is arranged in the shell 1, and the oil-gas separation membrane 22 blocks the detection port 11, the packaging of the gas sensor is completed. The gas sensor can be directly immersed in oil for gas detection, eliminating the degassing process and ensuring high efficiency and reliability.

[0084] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The content of this specification should not be understood as limiting the present invention.

Claims

1. A gas sensor for detecting parameters of gas in oil, characterized in that: include: A housing (1), wherein the housing (1) is provided with an inner cavity and a detection port (11) connected to the inner cavity; An oil-gas separation component (2) comprises a substrate (21) and an oil-gas separation membrane (22), wherein the substrate (21) is arranged in the inner cavity and has a loose and porous structure, and the oil-gas separation membrane (22) is arranged on a side of the substrate (21) facing the detection port (11) and blocks the detection port (11), and the oil-gas separation membrane (22) is configured to block the oil from passing through and allow the gas to be detected to pass through; A detection body (3) is arranged in the inner cavity and located on a side of the oil-gas separation component (2) away from the detection port (11). The detection body (3) includes an electrolyte (31) and a working electrode (32), a reference electrode (33) and a counter electrode (34) arranged in the electrolyte (31). The working electrode (32) is arranged at one end of the electrolyte (31) close to the detection port (11), and the reference electrode (33) and the counter electrode (34) are arranged at one end of the electrolyte (31) away from the detection port (11).

2. The gas sensor according to claim 1, characterized in that The microstructure of the oil-gas separation membrane (22) is a covalent organic framework structure, and the covalent organic framework has molecular pores, the molecular pores are larger than molecules of the gas, and the molecular pores are smaller than molecules of the oil.

3. The gas sensor according to claim 1, characterized in that: The gas sensor further comprises a protective film (4), wherein the protective film (4) is arranged between the oil-gas separation component (2) and the detection body (3), and the protective film (4) is configured to block the electrolyte (31) from passing through and allow the gas to be detected to pass through.

4. The gas sensor according to claim 3, characterized in that: Fixed structures (5) are provided on opposite sides of the protective film (4); the fixed structures (5) include a fixed net (51); and the fixed net (51) is fixedly connected to the protective film (4).

5. The gas sensor according to claim 4, characterized in that: The fixing structure (5) further comprises a sealing member (52), wherein the sealing member (52) is arranged around the outer circumference of the fixing net (51) to seal and connect the fixing net (51) and the side wall of the inner cavity.

6. The gas sensor according to claim 4, characterized in that: The housing (1) comprises a top surface (12) and a bottom surface (13) which are arranged opposite to each other. The detection port (11) is opened on the top surface (12). Along the direction from the top surface (12) to the bottom surface (13), the projection of the fixed net (51) on the bottom surface (13) is located within the projection of the working electrode (32) on the bottom surface (13).

7. A gas sensor packaging method, characterized in that: The packaging method is used to manufacture the gas sensor according to any one of claims 1 to 6, and the packaging method comprises: Get Base (21); Cleaning the substrate (21) with anhydrous ethanol; Drying the substrate (21) at a constant temperature for a first period of time; An oil-gas separation membrane (22) is coated on the surface of the dried substrate (21).

8. The gas sensor packaging method according to claim 7, characterized in that: Coating the oil-gas separation membrane (22) comprises: Coating the substrate (21) using a spin coater; Controlling the rotation speed of the spin coater to a first rotation speed and maintaining it for a second time period; Controlling the rotation speed of the spin coater to a second rotation speed and maintaining it for a third time period; The above steps are repeated several times to complete the coating of the oil-gas separation membrane (22).

9. The gas sensor packaging method according to claim 8, characterized in that: The packaging method further comprises: Allowing the substrate (21) coated with the oil-gas separation membrane (22) to stand for a fourth period of time; The substrate (21) is dried at a constant temperature and maintained for a fifth period of time.

10. The gas sensor packaging method according to claim 8, characterized in that: The first rotational speed is less than the second rotational speed; and / or The second duration is shorter than the third duration.

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